Background

 

 

Epidemiology                                                                                                                    

 

Third most common fracture after hip and distal radius

 

Etiology

 

FOOSH - mostly elderly patients with osteoporotic

Young patients - high energy MVA

 

Anatomy

 

Surgical neck - junction of diaphysis and metaphysis

Anatomical neck - junction of head and metaphysis

Neck shaft angle 130^o

Head retroverted 20^o relative to shaft

 

Blood supply 

 

Anterior humeral circumflex	Posterior Humeral circumflex	Rotator cuff
Major supply Anterolateral branch - runs in intertubercular groove lateral to biceps - becomes arcuate artery - supplies GT / LT / head	Small contribution posterior head Allows head to survive with both tuberosities fractured	Supplies blood to tuberosities in fractures
Nearly always disrupted in fractures

 

Neer Classification

 

Displaced fragments - > 1 cm displaced and/or > 45^o angulated

 

Number of parts - 2, 3 or 4

 

Two part	Three part	Four part
Surgical neck fracture Anatomical neck fracture Greater tuberosity fracture Lesser tuberosity fracture	Surgical neck + greater tuberosity Surgical neck + lesser tuberosity	Surgical neck + GT + LT
Fracture dislocations	Fracture dislocations Head split	Fracture dislocations

 

Two part

 

Displaced greater tuberosity fracture

 

Displaced lesser tuberosity fracture

 

Two part proximal humerus fracture

 

Two part proximal humerus fracture dislocation posterior

 

Three part

 

Three part with greater tuberosity fracture

 

Three part fracture dislocation anterior

 

Three part fracture dislocation with anatomical neck

 

Three part head splitting fracture

 

Four part

 

 

 

 

 

Avascular necrosis (AVN)

 

 

In most fractures, arcuate artery is disrupted, but head survives

- posterior circumflex artery is sufficient

- risk increases with amount of displacement

- 4 part fracture 30%

- 3 part fracture 15%

 

Hertel et al J Should Elbow Surg 2004

 

2 criteria to predict ischaemia

A. Metaphyseal head extension < 8 mm

B. Medial hinge displaced > 2mm

 

97% positive predictive of ischemia if both factors present

 

Deforming Forces

 

2 part fracture	Greater tuberosity fracture	Lesser tuberosity fracture
Pectoralis major displaces shaft medially Head internally rotated by SSC	Fragment pulled postero-superior Combination of SS / IS / T minor	Displaced medially by subscapularis

 

 

 

 

 

 

 

 

 

 

 

 

 

X-rays

 

AP / Scapula Lateral / Axillary lateral

 

CT 

 

Assess

- number of fracture fragements

- degree of displacement

- head splitting fracture

- is there sufficient bone in humeral head to consider ORIF?

 

 

Associated Injuries

 

Axillary nerve 

- most commonly injured as close proximity 

- relatively fixed by posterior cord brachial plexus & deltoid

 

Axillary artery

- in young patient with high speed injury

- can have collateral circulation and pink hand

 

Management

 

Non operative 

 

Indications

 

Minimally displaced

Elderly / low functioning patients

 

Results

 

Koval et al JBJS Am 1997

- 104 patients minimally displaced fracture as per Neer

- < 1cm displacement and <45^o

- 90% no pain, 77% good or excellent result

- ROM approximately 90% of the other side

- 10% moderate pain and 10% poor result

- poor function and ROM associated with phyio started > 14 days after injury

- poor function associated with pre-existing cuff problems

 

Olerudet al JSES 2011

- RCT nonop v hemiarthroplasty for displaced 4 part

- 55 patients, average age 77

- 2 year follow up

- significant advantage of hemiarthroplasty

 

Complications of nonoperative treatment

 

Non-union

 

Uncommon

- associated with AVN

 

 

Malunion OA

 

 

TSR / consider resurfacing if significant deformity

- can be difficult surgery due to abnormal anatomy